Monday, November 7, 2011

Why Mike Richter Might Be Overrated

Mike Richter is a goalie that is remembered pretty fondly by many. That shouldn't be too surprising, as he played a long career on a big market team, he won a Cup, and he represented the U.S.A. admirably in a number of international tournaments. However, looking at his career numbers and especially his Vezina and All-Star voting record makes it pretty clear that Richter was not a member of the goaltending elite. Pretty much the only thing that was elite was his paycheque; in his entire career nobody ever gave Richter a first place vote for the postseason All-Star teams.

I recently realized, however, that Richter may not even have been as good as his numbers suggest. The reason is that there is some evidence that Richter may have benefited from a generous home scorer during the prime of his career in New York. Madison Square Garden has long been known as a rink that produces abnormal statistics for things like shot distance. During the mid-1990s, they might have been recording some screwy numbers when it comes to total shots as well.

For seven consecutive seasons from 1991-92 to 1997-98, Mike Richter's backup goalies faced a higher rate of shots against at home than on the road. Richter faced a higher rate himself in five out of the seven seasons and narrowly missed the two other times, finishing 0.8 lower in '91-92 and 0.5 lower in '97-98. Having a higher rate of shots against at home in any season is relatively rare, given that teams typically play better at home. When it happens seven years in a row, it is a major outlier.

Richter ('92-'98):

Home: 99-60-24, 2.71, .911, 30.5 SA/60

Road: 71-66-13, 3.01, .896, 29.1 SA/60

NYR backup goalies ('92 to '98):

Home: 45-25-18, 2.81, .910, 31.2 SA/60

Road: 47-60-14, 3.01, .894, 28.4 SA/60

The home/road GAA splits are quite normal. The backups had a very skewed record at home vs. on the road, which implies that the Rangers played a lot better in front of them at home. Given that, one would not expect shots against to go up by nearly 3 per game. The only effect that could somewhat account for that would be score effects. The Rangers playing to the score might explain why the backups had more of a differential between home and road than Richter did, but Richter himself had a more typical home/road split yet still had a higher shots against rate at home. Thus it seems that all Rangers goalies were getting extra credit for saves at MSG.

It is at least possible that the Rangers played a very high event game at home, although if that were true it would be expected that the goalie's home save percentages would have dropped or stayed the same rather than rose substantially compared to their numbers on the road.

Richter's numbers at home and on the road were almost identical to those of his backups. For a several of those seasons that was nothing to be ashamed of, as quality veteran John Vanbiesbrouck was Richter's playing partner, but for the rest of it the Rangers had a fairly undistinguished collection of backups, led by Glenn Healy. Healy's numbers cratered once he left the Rangers to play on the Leafs, which probably had a lot to do with age, but may have also had something to do with artificially inflated home numbers.

League average over the period was roughly .898. Richter's overall save percentage checked in at .905, suggesting that he was a pretty valuable goalie, worth nearly two wins above average to his team per season. However, the numbers show that nearly all of his excess value was coming based on the performance he recorded on home ice.

If we assume that in reality Richter faced the same rate of shots against at home and on the road and that the difference was due to generous scorekeeping, his home save percentage would drop to .907 and his overall save percentage for the period would fall to .902. If Richter actually faced one fewer shot against per 60 minutes at home, his numbers would fall even further to .904 at home and .900 overall, a result that would leave him about 20 goals above an average goalie. That's still pretty good, but it would have a pretty dramatic impact on Richter's career numbers. It would cost him about half of his career value in terms of goals above average, causing him to plunge well out of the "decent starters" range on this list.

On the road, Mike Richter was almost exactly an average goalie, based on his save percentage numbers. At home, his numbers were up among the best in the league. Given that the numbers of his backups followed the same pattern, it seems unreasonable to conclude that this was due to anything related to Richter himself. Furthermore, it seems unlikely that the Rangers would have been successfully suppressing shot quality against at least 10% better than an average team while playing at home yet for some reason choosing not to do the same thing on the road. Perhaps there were some team effects, but on the whole it seems like the best explanation is probably that there was some degree of shot padding at Madison Square Garden in the mid-1990s which boosted Mike Richter's statistics.

9 comments:

Interesting post but there seems to be some major fuzzy logic and mere speculation employed here.

Madison Square Garden has long been known as a rink that produces abnormal statistics for things like shot distance. During the mid-1990s, they might have been recording some screwy numbers when it comes to total shots as well.

Might?

Having a higher rate of shots against at home in any season is relatively rare, given that teams typically play better at home.

I thought playing better resulted in winning. Never knew it meant the other team shoots less.

The home/road GAA splits are quite normal. The backups had a very skewed record at home vs. on the road, which implies that the Rangers played a lot better in front of them at home. Given that, one would not expect shots against to go up by nearly 3 per game.

Again, how do you make the leap from the Rangers playing better to the other team shooting less? By your logic, that means that any team that wins a game (through better play, right?) has more shots than the losing team 100% of the time.

The only effect that could somewhat account for that would be score effects.

Yup, that's the only possible explanation that could account for this. It's a wrap! Let's get this guy on Cold Case!

Don't know why Lundqvist is generally regarded as the best goalie in hockey. Don't these hockey loving idiots know his stats are mere illusion? He isn't nearly as good as people think. It's the Garden buffing his stats!

Jagr Bombs: There is certainly speculation being applied here, because scorer bias is very difficult to conclusively prove. Some teams play better at home, some teams play a different style of game at home, sometimes the official scorer gets replaced or changes the way he records the game. It's hard to tease out in the data, but when a team's numbers deviate significantly from the norm over multiple seasons then there is good reason to question whether it might be a factor.

Again, how do you make the leap from the Rangers playing better to the other team shooting less? By your logic, that means that any team that wins a game (through better play, right?) has more shots than the losing team 100% of the time.

In the aggregate, teams that outshoot the opposition tend to win games. That only has to be generally true for my logic to apply. But I'll freely admit I'm speculating about score effects in New York because I haven't done the statistical breakdown for save percentage or shots against by score for that period.

Finally, who said anything about Lundqvist? My arguments only apply to Richter, as I haven't seen any compelling evidence of shot padding in New York since the lockout. Here are the same numbers for Lundqvist in his career:

Home: .919, 27.3 SA/60Road: .918, 29.9 SA/60

That's an normal home/road split for a goalie. Compare that to Richter's numbers, and you'll see why my suspicions are there.

When talking about Mike Richter I think he gets a benefit form a couple things.

1) During his time he was arguably the best US born goalie around. This, as you said, got him a lot of international competition ice time and a lot of pop from US media.

2) He made a lot of highlight reel saves (like the penalty shot save on Bure).

I would consider him almost like a Fuhr guy in a more competitive environment. He played on some pretty good teams and had quite a bit of personal success. At the same time he was a very athletic guy who when you saw game highlights looked really good doing it.

92-98 was also the peak of the dead-puck era, when half the NHL would get a one-goal lead and go into a five-man defensive shell for the rest of the game. I would expect any goalie in this era would have faced more shots in a game he was winning - and a goalie with a notably higher win ratio at home to have faced more shots at home. That could certainly explain the differential you're seeing - the question is whether goaltenders for other teams with similar home/road win differentials in that era also had similar differences in shot totals.

About Me

I'm Philip Myrland, goalie stats blogger since 2007 and former writer for Hockey Prospectus. I call myself a contrarian because I rely mainly on stats-based analysis, think large sample sizes are more important than "big saves" and prefer to rank goalies based on save percentage rather than team success. In other words, pretty much the mainstream views of the hockey analytics community, but I've grown attached to the handle and plan to keep it as long as broadcasters everywhere keep bringing up GAA and wins. If you have any questions or comments contact me by email (contrariangoaltender@gmail.com). You can also follow me on Twitter (@tcghockey).